Influenza Vaccination During Pregnancy: A Narrative Review on Maternal and Neonatal Outcomes Associated with Seasonal Influenza Infection

Seasonal influenza remains an important public health concern worldwide, and pregnant women represent a particularly vulnerable population due to physiological and immunological changes associated with gestation. Influenza infection during pregnancy has been associated with adverse maternal, fetal and neonatal outcomes. This narrative review summarizes current evidence regarding maternal influenza infection and influenza vaccination during pregnancy. A structured literature search was conducted using PubMed, Embase and Cochrane Library databases. Studies published between 2020 and 2025 addressing maternal influenza infection, pregnancy outcomes and influenza vaccination were reviewed. Current evidence suggests that maternal influenza infection is associated with increased risks of spontaneous abortion, preterm birth, hospitalization and congenital malformations, especially neural tube defects and congenital heart defects when infection occurs during the first trimester. In contrast, evidence regarding long-term neurodevelopmental outcomes remains inconsistent. Influenza vaccination during pregnancy demonstrates moderate-to-high effectiveness in preventing maternal and neonatal influenza infection and shows a favorable safety profile. Available evidence also suggests that neuraminidase inhibitors, particularly oseltamivir, can be used safely during pregnancy without increasing the risk of congenital malformations or adverse neonatal outcomes. Influenza vaccination during pregnancy should continue to be promoted as a safe and effective public health strategy to protect both mothers and infants.